Field of the Invention
The invention relates to methods for manufacturing semiconductor devices. More specifically, the invention relates to formation of electrically conductive interconnects through one or more dielectric material layers.
Description of Related Art
Semiconductor devices are formed in a multi-level arrangement with electrically conductive structures in different levels insulated from each other by one or more intervening levels of dielectric material. Required electrical connectivity between conductive structures in different levels is provided by interlevel conductors, such as vias and contacts, that extend through the dielectric material. As semiconductor devices continue to scale downward in size, the aspect ratio (i.e., ratio of height to width) of the interlevel conductors becomes greater, even to the point where uniformity in material presence and/or density of the interlevel conductor is difficult to achieve. It is within this context that the present invention arises.